Wednesday, November 23, 2016

Mapping Montreal's Hot Spot of Crime

The Rue Sainte-Catherine Ouest is the robbery center of Montreal. At least that is one conclusion that can be drawn from a new interactive crime map of the city.

Vue Sur la Sécurité Publique is an interactive map of crimes reported to the police in Montreal since the beginning of 2015. The map allows you to view the locations of a number of different crimes that have been reported to the police over the last two years.

Using the map's filter controls you can select different date ranges and also view different types of crime on the map. If you select to view only the crime of theft ('vol qualifie') the map reveals a distinct hot-spot of crime all along the Rue Sainte-Catherine Ouest.

One of the dangers of crime maps is that neighborhoods and streets may be stigmatized as hot-spots of crime based on inaccurate data The accuracy of crime data depends on a number of different factors, including victims actually reporting crime, the police accurately recording the data and the data being accurately plotted to the correct location.

The danger of errors in mapping crime was highlighted in this Seismograph San Francisco Bike Theft Map. While creating a map of bike thefts in San Francisco Seismograph found that 850 Bryant Street was a curious hot-spot of bike crime in the Californian city. It turns out that 850 Bryant Street is actually the address of a police station. Stolen bikes with no location data were simply
plotted by the police to the address of the reporting police station. 850 Bryant Street is therefore the bike theft equivalent of Null Island in San Francisco and not a real hot-spot of stolen bikes.

It is entirely possible therefore that the Rue Sainte-Catherine Ouest in Montreal is not a cesspit of crime. I strongly suspect that the curiously large number of thefts on the Rue Sainte-Catherine Ouest is a result of an anomaly in the way that crime is reported to or recorded by the police in Montreal.